-LRB- CNN -RRB- -- Philippine seismologists issued an alert on Mount Bulusan Sunday after the Luzon Island volcano erupted twice during a 24-hour period , according to a bulletin released by the nation 's volcano-monitoring agency .

However , the Philippine Institute of Volcanology and Seismology -LRB- PHILVOCS -RRB- said the eruptions posed little threat to the villages surrounding the Luzon Island volcano . Most of the villages lie outside the 4-kilometer -LRB- 2 1/2 - mile -RRB- danger zone , the bulletin stated .

Philippine volcanologists , according to the agency , are n't expecting Mount Bulusan to erupt again soon . The volcano is located about 249 kilometers -LRB- 155 miles -RRB- southeast of Manila .

The area immediately surrounding the Bulusan Volcano is mostly rural . There are several villages , but most are outside the danger zone , according to PHILVOCS . The most recent eruption , which took place before dawn local time on Sunday lasted about 20 minutes , according to the agency .

In declaring an `` Alert Level 1 , '' the agency warned nearby residents not to enter the 4-kilometer `` permanent danger zone '' because of possible steam and ash explosions . Area residents were also warned of the possibility of flooding if heavy rains push sediment-filled streams out of their banks .

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Philippine seismologists declare Alert Level 1 for Mount Bulusan volcano

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Volcano erupted twice in 24 hours

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Nearby villagers warned to stay out of `` permanent danger zone ''